AB1306 AA AMYLOIDOSIS IN CHRONIC RHEUMATIC DISEASES: ABOUT 20 CASES
Authors: M. Ardhaoui, J. Mahbouba, M. Ghali, F. Fhima, N. Ben Chekaya, S. Zrour, I. Bejia, M. Touzi, N. Bergaoui
Journal: Annals of the Rheumatic Diseases (2022)

Background Secondary AA amyloidosis is a complication of certain uncontrolled chronic inflammatory rheumatic diseases. The diagnosis of AA amyloidosis is anatomo-pathological based on the detection of amyloid deposits within a biopsy specimen. Objectives The aim of this study is to determine the clinical, biological, therapeutic and evolutionary aspects of amyloidosis during these diseases. Methods This is a retrospective descriptive study conducted in the rheumatology department in Monastir, Tunisia, including patients followed for chronic inflammatory rheumatism complicated by AA amyloidosis. Results Our study included 20 patients (13 women and 7 men). Their mean age at the time of diagnosis of amyloidosis was 55.4 years [18-76]. The rheumatic diseases were: Rheumatoid Arthritis (RA) in 13 cases (65%), Ankylosing Spondylitis in 3 cases (15 %), Behçet’s disease in 2 cases and Juvenile idiopathic arthritis in its systemic form in 2 cases (10% for both). Amyloidosis occurred after a mean duration of rheumatic disease of 11.5 years [3-27]. The mean sedimentation rate at diagnosis of amyloidosis was 100.5 mm per hour [21-131]. The mean C-reactive protein at diagnosis was 38.35 mg/L [1.4-135]. Inaugural manifestations of amyloidosis were: edema of lower limbs in 8 cases, nephrotic syndrome in 7 cases, renal failure in 4 cases and an abdominal clinical presentation (diarrhea and abdominal pain) associated with proteinuria in 2 cases. Proteinuria was constant, with a mean level of 7.5 g/24 h [3.5-20]. It was isolated in 5 cases. Amyloidosis was subclinical in 2 cases and was discovered by an abdominal fat biopsy performed during a research protocol. The diagnosis was confirmed by: renal biopsy (n=9), rectal biopsy (n=5), salivary gland biopsy (n=4) and abdominal fat biopsy (n=2). Amyloidosis extension was assessed for 50% of our patients. Cardiac involvement was the most frequent, revealed in 5 patients. Concentric left ventricular hypertrophy was found in 4 patients. Pulmonary arterial hypertension and pericardial effusion were found in 1 case. Hepatic involvement was detected in 2 cases in the form of hepatomegaly without disturbance of liver function tests. Adrenal gland involvement was detected in 1 case with homogeneous hypertrophy of the adrenal glands associated with adrenal dysfunction. Only 1 patient had peripheral nerve damage in the form of bilateral carpal tunnel syndrome. Concerning the treatment; 12 patients received Colchicine. Chloraminophen was tried for 4 patients with amyloidosis secondary to RA and Azathioprine for one patient with RA. The evolution was unfavorable in 6 cases marked by death within a mean time of 3.4 years. Conclusion Although its prevalence is decreasing, owing to therapeutic progress in chronic rheumatic diseases, AA amyloidosis remains a not exceptional complication. It has a poor prognosis, particularly because of renal disease and cardiac involvement. Disclosure of Interests None declared